Edge-holding- device itos sheet glass



. Nov. 4 192.4. 1,514,338

J. H. REDSHAW EDGE HOLDING DEVICE FOR SHEET GLASS Filed Sept. 11

3 Sheets-Sheet 1 I I I I I I 1 I 1 I i I I 1 I I I I x I 1 I/ I 1, 1 I I f I I I I I I l INVENTOR Nov. 4 1924. J. H. REDSHAW EDGE HOLDING DEVICE FOR SHEET GLASS Filed Sent. 11. I923 JSheeta-Sheet 2 INVENTOR 2%. @W 4 Ncfir. 4, 1924. 1,514,338

J. H REDSHAW EDGE HOLDING DEVICE FOR SHEET GLASS Patented Nov. d, lillild-i llltlllttll New hlfltitlt to ltilllllll' tittarta To all whom, it may concern:

Be it known that it, dossier-r li-l. ltnnsr-raw, a citizen ot the llnitcd States, and a resident of Pittsburgh, in the county oi Allegheny and titate owl llennsylvania, have made a new and useful invention in improvements in llldge-l-loldinn' Devices tor tihect Glass, oil which the following; is a specification.

The invention relates to apparatus :tor use with a sheet drawing machine, and particularly to the form shown in the applica tion oi Harry ii'lli @llinglutt, Serial No. 621,- 186, tiled February 26., 1923, which involves the use of stroking lingers operated from a suitable driving; means or motor, and adapted to straddle the crit cs ot' the sheet at its base to thin them and prevent them from gradually working inward. With this form of apparatus, ditticulty experienced in adjusting the mechan n so that the stroking lingers exercise just the right amount of holding effect, as this depends more or less on the condition ot the glass bath wl'iich varies, so that under some conditions the glass at the edges may be worked out and chilled to too great an extent, while under other conditions the edgres may worlr inward despite the action of the lingers.

This condition calls for a close supervision of the device and more or less adjustment oi the frequency of the stroke, or oi its character, from time to time. The object of this invention is to overcome this objection as to continued attention and adjust-- ment by the provision of means whereby the actuation of the machine is controlled by the position of the edge oi the glass sheetbeinp; drawn.

Briefly stated, this preferably accomplished by the use of a device, which contacts with the edge of the sheet a short dis tance above the glass and which is so arranged that when the edge moves out beyond its predetermined position, the move-' ment of the driving mechanism of the lingers is stopped and when such edge moves in. beyond a predetermined point, the movement of such mechanism is started again. The invention is not restricted to means for stopping and starting; the driving; mechanism, (although this the preferred method of operation), but contemplates as well, the speeding up or slowing down 0? the mechanism, or adj sting the stroke ot the fingers by the movements of the governing device which contacts with the edge of the sheet. in thisway the requirement for the continuum; supervision and adjustment oi? the apparatus avoided. One embodiment of the invention is illustrated. in the accompanying drawings wherein:

l igure Il. a diagrammatic side elevation showing; the drawing apparatus with which the edge l'iolding mechanism constituting the present invention is preferably used. hip 2 is a side elevation oi the edge holding device. 3 is a rear elevation of the edge holding; device. And Fig. 4

a diagrammatic view showing the electrical connections.

ltleferring first to the 'eneral arrangement oil parts as illustrated in Fig. 1, the principal parts of the drawing apparatus a re enumerated as follows: 1 is the drawing tanlr or extension, carrying; a molten bath ct glass 2 in communication with a suitable melting tank 3; l and 5 are endless belts, preferably oi: asbestos fabric for continuously drawin the sheet of glass 6 from the molten bath; 7 and 8 are the driving pulleys tor the belts, such pulleys being driven from a suitable motor, not shown; 9 and 1.0 are solid steel bars circular in cross section lying); in the lower ends of the belts and serving}; by reason of their weight to hold the belts in tension; 11 are a series of rolls back ot the inner flights of the belts tor pressing the belts against the glass, such rolls be" held inward by means of springs ts, not shown; 12 and 13 are pairs or we of driven rollers covered with asbestos for assisting: in the pulling of the sheet; and 1a is one of the edge holding devices to which the present invention is particularly directed, it being; understood, however, that the edge holding mechanism may be used in connection with any form of drawingmeclr anism. it will be understood also that an edge holding; device, such as that shown in 2 applied at each side of the sheet,

but for brevity of description and illustra tion, only one oi such devices is shown. The edge holding; device comprises a base 15, a pair of lever arms 16 pivotally mounted at 17 upon the base; a second lever arm 18 pivotally mounted at 19 upon the upper ends of the arms 16; a bar 20 which is jiGlJliQQlEtt its lower end to provide a pair and 30 for holdingtherolls 31 and 32in engagement with the cams; a switch 33 (Fig. 4) for starting and stopping the motor; and circuit breaking devices in the casings 34 and 35 for controlling the switch The rod 20 is detachably mounted in the end of the rod 36,-being"held in position by means-ottheset 'screws37, and the rod 36 may.:-be adjusted in thelever arm 18 by means of-K-the handw'heel 38 whose hub is threaded upon thevscrew threaded rear end of the-rod36.- In this manner the position of-the fingersQl may be-adjusted to meet requirements. In order that the fingers 2i mayirhatea yieldingrenga'gement with the glassgcthef-arm l8 which is pivoted upon the upperaendswt'the leverarms "16 is maintained in operative'position by 'meansof the spring 391bearingwaga-inst theend of the lever at one end and resting at its other end againstthelever 40 alsoi-pivoted'at 19 and carrying the roller 32 heretofore-referred to.

-The spring 39 is held in position by means of thevboltv 41 whichqextends through the two leversand is provided with they nuts 42 and --43;- the-lowerend "ofxthe bolt being fOI'H'lBdcllifiO. an eye which-is engaged by the-spring30fi The cams and levers-areso proportioned that-the, rotation of the shaft- 26 gives the fingers 21-the5desired path ot -movement for preventing.inwardmovement of the'edge of thersheet 6'at' -its base. This path of movement'iis-indicated' by'the -dot and dash" line A of F ig.;2, this being the path of the point B, which: is the center of curvature-of the fingers. This path" of movement *may be modi'fied by shifting the position'of the earns 27 and-28 aboutthe shaft 26 or by modifying"tl1e -sl1ape-'o f such cams; It may also be-adjustedby changing the position of the roller/32 which roller is carried by the sliding-blocks 44 mounted in-slots'in-the end of thelever; arm--40. :Athreaded stem 45 is attaehednto these Tblocksrand may be adj ust ed 'byimeansief the; handwheel :46 swiveled Gurrerit is --supplied" to the imotor 22 by circuit including the wires :52: and 53; This circuit talsodncludes the circuit breaker -34.

This circuit breaker comprises the contact members 54 and 55 normally held in contact by means of the spring 56. The member 55 is pivoted at 57 and is provided with a recurved arm 58 carrying a grooved roller 59 for engaging the edge of the. sheet 6. If

the edge of the glass sheet under the influence of the stroking fingers 21 moves outwardly beyond a predetermined point, the arm53 is pushed outwardly, thus swinging the contact member 55 downward and breaking the circuit through the connections 54 and 55. This permits the spring 52 to move the contact member 49 (Fig. 4) to the'lei't so that the flow of current through the leads 1? and 48 to the motor is discontinued. However, in order to guard against the stopping of the motor while the fingers 21 are still in the glass another circuit includ ing the connections 60 and 61 and the circuit breaker 35 is employed. As indicated in Pig. 1 this circult breaker includes the con tact members 62 and 63, the spring 64 normally tending to press the member 63 downward out of contact with the member 62 and the Zllill 65 provided with the roller 66 engaging the lever arm 16. The members 63 and 65 are integral and are pivotally supported at 67. When in its forward position as illustrated in Fig. 2, the lever arm 1.6

permit the member 65 to also move to the rightso that the member 63 moves downward out of contact with the member 62. At this timethe fingers 21 have been moved out of the glass along the path A to their extreme left hand position. The motor now stops sinc the flow of current through the circuit breaker is discontinued and the current is cut oil from the magnet 51 so that the contact member 49 is opened by the .spring'52j The parts remain in this position-until the circuit breaker 34 is again closed. This will occur in. due course, as

.the edge of the sheet "6 will tend to gradw ally work to theright as the drawing continues and finally the roller 59 will move '-in' sufiicientlyto permit the spring 56 to bringtheinember 55 into contactwith the -member-54. The circuit through the mag; net 51 is thus completed and the contact 1 member 49 will be closed, thus completing the circuit between the leads 47and 48 so that the motor again begins to operate. This operation will continue until the edge of the sheet again works out to a point such as-to causethe breakingof the contactbe-- lll) tween the members 54: and 55 when the machine will again be stoppeduntil the edge of the sheet works back to its proper position.

What I claim is:

1. The combination with apparatus for drawing a sheet of glassfrom a molten bath, of means for preventing the inward movement of the edge of the sheet comprising a pair of fingers spaced apart to receive the edge of the sheet, and driving means "for moving the fingers at intervals downward into the glass bath and outward, and a device controlled by the position of the edge of the sheet for governing the actuation oi? said driving means.

2. The combination with apparatus for drawmg a sheet of glass itrom a molten bath,

of means for preventing the inward movement of the edge oi the sheet comprising a pair of fingers spaced apart to receive the edge of the sheet, and driving means for moving the fingers at intervals downward into the glass bath and outward, and a device controlled by the position of the edge of the sheet for starting and stopping the actuation of said driving means.

3. The combination with apparatus tor drawing a sheet oi glass from a molten bath, oi. means for preventing the inward movement of the edge of the sheet comprising a pair of fingers spaced apart to receive the edge of the sheet, and driving means for moving the fingers at intervals downward into the glass bath and outward, and a device controlled by the position of the edge ot the sheet for governing the actuation of said driving means, saiddevice including a member yieldingly held against such edge of the sheet.

4, The combination with apparatus tor drawing a sheet of glass from a molten bath. of means for preventing the inward movement of the edge of the sheet comprising a pair of fingers spaced apart to receive the edge of the sheet, and driving means for moving the fingers at intervals downward into the glass bath and outward, and a device controlled by the position of the edge of the sheet for starting and stopping the actuation oi? said driving means, said device including a member yieldingly held against such edge of the sheet.

5. The combination with apparatus for drawing a sheet of glass from a molten bath, of means :t'or preventing the inward move ment oi the edge oi? the sheet comprising a pair of fingers spaced apart to receive the edge of the sheet, and driving means including an electric motor for moving the fingers at intervals downward into the glass bath and outward, and a device controlled by the position oi the edge oi? the sheet for governin the supply of current to said motor.

6, The combination with apparatus for d raw ing a sheet of gldSf-J from a molten bath, of means tor preventing the inward move ment of the edge otthe sheet comprising a pair oil :[ingers spaced. apart to receive the edge of the sheet, and driving means including an electric motor for moving the fingers at intervals downward into the glass bath and outward, and a device comprising a member yieldingly pressed against the edge ot the sheet and a switch operated therefrom for governing the supply of current to said motor so that the motor is stopped when the edge moves out beyond a predetermined point and is started when it moves in beyond a predetermined point.

7. The combination with apparatus for drawing a sheet of glass from a molten bath, of means for preventing the inward move ment of the edge of the sheet comprising a pair of fingers spaced apart to receive the edge of the sheet, and driving means including an electric motor for moving the fingers at intervals downward into the glass bath and outward, a device comprising a member yieldingly pressed against the edge of the sheet and a switch operable therefrom for governing the supply of current to said motor so that the motor is stopped when the edge moves out beyond a predetermined point, and. is started when it moves in beyond a predetermined point, and means for prevent ing the stopping of the motor until said fingers are withdrawn from the glass bath.

In testimony whereof, I have hereunto subscribed my name this 28th day of August,

JOtEiEPI-I H. ltlilDSl-IAN. 

